Spotting TrendsThe Wisdom of the Few

Xiaolan Sha◦ Daniele Quercia✦Pietro Michiardi•

Matteo Dell’Amico•

Our Work

What are the trends one might be interested in?

What Is a Trend

Trending

≠Popular

Who Create Trends

Trend Makers

Trend Spotters｛

Influentials

Accidental｝A COMBINED

PROCESS

(upload)

(vote)

Our Context

SPECIALTechnology-Savvy

Design-Conscious

9,316 users, 6,395 items and 21,252 votes

Our Context

A core group of users are main content contributors.

Traditional

Preference Matrix

p(u,i) = 1 if u likes i, otherwise 0item i

user u

Recommend

ALG

OR

ITH

M

Items

Users

Trend-awareRecommendation

User Space

Trend Spotters

Trend Makers

Recommend Trends

Identify Trends

Item Space

Our Approach

A Special Few

｛Activity

Content

Social Network

Geography

Features

SVMUser Space

Trend Spotters

Trend Makers

?

A Special Few

｛if uploaders are trend makers of any quality

if voters are trend spotters - only of high quality

Logistic Regression

Trends

Item Space

?

Trend-aware

Trends

Trend Space

Trend-aware Preference Matrix

p(u,i) = 1 if u likes trend itrend i

user u

Recommend Trends

SVD

Trend-awareRecommendation

User Space

Trend Spotters

Trend Makers

Recommend Trends

Identify Trends

Item Space

Our Approach

Preference Matrix

p(u,i) = 1 if u likes i and item i is a trend, otherwise 0

item i

user u

Recommend

ALG

OR

ITH

M

Items

Users

Baseline

Evaluation

Recall(N) = #hits / |T|Precision(N) = #hits / (N * |T|)

Summary

Popular ≠ Trends

Trend Spotters & Makers Exist ! Identify them improve the recommendation.

Spotting Trends: The Wisdom of the FewXiaolan Sha, Daniele Quercia, Pietro Michiardi, Matteo Dell’Amico

Thank You!